• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.9
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• pp.671-680
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• 2020

This paper describes an improved beam analysis for compound rotorcraft fuselage design. The present beam approach is capable of analyzing fuselage composed of stiffeners using equivalent layer methodology. Thickness of the skin and laminated layer approach are suggested based on the unified beam formulation. The analysis which considers an equivalent stiffener layer is performed for a fuselage with stiffeners and preliminary study about the specification of stiffeners is conducted and compared by the results using the existing software.

• Journal of Korean Society for Geospatial Information Science
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• v.4 no.2 s.8
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• pp.47-54
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• 1996

It needs more than two images which are obtained in real time to decide 3D positioning of dynamic object. Though we use digital camera which is became wide utilization, but it can't obtain sequential image. So, in this study, we constructed momentary image acquisition system using video camera. Also, we took a photograph of LCD timer and dynamic object together for real time stereo image, and we obtained independent digital image from sequential image using video editor. As a result of the study, we could obtain the independent image as true color digital image of $788{\times}550$pixels with 1/100sec accuracy in the same time. And it was good when we tested object target. For comparing 3D positioning accuracy, we could obtained negative with metric camera using B-shutter.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.37-39
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• 2007

고속 활주형선의 선형시험 ${\cdot}$ 검증을 위하여 설 해상모형시험기법을 정립하였으며, 본 시험법을 이용하여 선미 보조동체 장착 유무에 따른 고속 Stepped Hull 선형의 횡동요 및 저항특성을 비교, 분석하였다.

• Journal of Korea Ship Safrty Technology Authority
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• v.16
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• pp.38-52
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• 2004

쌍동선이나 삼동선과 같은 다동체를 가진 선박의 선형과 유체 동력학적 특징들에 대하여는 실험과 동시에 수치적으로 널리 연구되어 왔다. 본 연구는 소형 다동체 레저낚시어선의 선형개발에 관한 연구로서 모형실험은 인하대학교 선형시험구조에서 수행되었으며 수치계산은 Euler 방정식의 유한차분해법이 이용되었다.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1740-1741
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• 2007

본 논문은 이족 로봇에서의 효과적으로 동체를 탐지하는 방법에 대하여 논한다. 이족 로봇의 움직임은 모바일 로봇의 움직임과는 달리 종횡의 움직임이 동시에 나타나게 된다. 따라서 로봇의 비젼이 움직이는 상황에서 움직이는 물체를 탐지해야 한다. 따라서 본 논문에서는 로봇의 움직임을 분석하여 로봇의 움직임을 보정하여 보다 높은 성능의 동체 탐지 성능을 높였다. 제안된 방법을 실제의 로봇으로부터의 영상을 통하여 실험한 결과 우수한 탐지 성능을 얻을 수 있었다.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.8-15
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• 2006

In this report Smart UAV structural analysis of the aft fuselage is presented. Aft fuselage needs to have enough strength and stiffness considering loads of the Vertical and Horizontal Stabilizer together. It has a big hole for the purpose of engine exhaust duct on its side body. In addition, much attention is needed in high temperature region due to material strength deterioration.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.265-270
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• 2010

This paper presents the rocket motor support structure to position solid rocket engine within a missile fuselage. When the rocket motor is mounted inside a missile fuselage, fuselage structure must be designed to withstand various structural problems resulting from inserted rocket motor such as axial thrust force, shock/vibration, axial deformation of the rocket motor tank in addition to the flight loads. The motor support structure system proposed in this paper proved to be very simple and efficient while satisfying all the design requirements.

• The Korean Journal of Malacology
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• v.31 no.4
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• pp.315-322
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• 2015

The sex of bivalves is classified into gonochorism and hermaphroditism, and hermaphroditism is further divided into simultaneous (synchronous or functional), and sequential (asynchronous). The sequential hermaphroditism signifies sex reversal in accordance with seasons. In general, in the case of gonochoristic bivalves, manifestation of sex as female and male, after having identified the morphological sex, is limited to a period of the life cycle in any given individual. In order to accurately identify sex, continuous monitoring of changes in the sex during life cycle is necessary by tagging the sex. In the bivalves, sex reversal and sequential hermaphroditism has been reported in the Ostreidae, Pectinidae, Veneridae and Arcidae etc.. Most of these studies have reached this conclusion based on evidence derived from sex ratio change in accordance with the age within same populations. Sex change in the sequential hermaphroditic bivalves normally occurs when the gonad is undifferentiated between spawning seasons. Two factors are involved in sex determination and sex change in bivalves, namely genetic and environmental. However, more detailed research is needed on the effect of the genetic and environmental factors involved in sex determination and sex change of bivalves.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.12
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• pp.9-17
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• 2005

An experimental study of the vortical flow over a yawed delta wing with leading edge extension(LEX) was conducted to investigate the effects of the existence of a centerbody configuration on the flow characteristics of the wing and LEX vortices using off-surface visualization and PIV measurements. The qualitative investigation using these two techniques indicated that the effect of the centerbody existence on the vortex formation was minimal at somewhat low range of angles of attack and sideslip angles. However, the quantitative analysis of the surface pressure measurements revealed the effect of centerbody existence to be prominently increased for the cases with higher angles of attack and sideslip angles. It was also found that the centerbody effect was not significant compared to the effect of sideslip for the present LEX-delta wing configuration.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.12
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• pp.1070-1079
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• 2012

The impact energy absorbing is a very important characteristic of an aircraft to enhance the survivability of occupants when an aircraft is under the survivable accident such as an emergency landing condition. The impact energy is generally transmitted into the occupant and absorbed through a landing gear, a subfloor (lower structure of fuselage), and a seat. The characteristic of crash energy absorbing of a subfloor depends on the type of an aircraft, a shape of structure, and an applied material. Therefore, the study of crashworthiness characteristics of a subfloor structure is very important work to improve the safety of an aircraft. In this study, a finite element model of a narrow body fuselage section for the 80~90 seats regional aircraft was developed and crash simulation was executed using an explicit finite element analysis. Through survey of the impact energy distribution of each structural part of a fuselage and floor-level acceleration response, the crashworthiness characteristics and performance was evaluated.